Sewing-machine.



G. W. NELSON.

SEWING MACHINE.

APPLICATION FILED MAR. 2. 1912.

Patented Dec. 24, 1918.

7SHEETS-SHEET I.

m 5 m w W If rm v e. w. NELSON.

SEWING MACHINE.

APPLICATION FILED MAR. 2. 1912.

Patented Dec. 24, 1918.

7SHEETSSHEET 2.

WITNESSES:

G. W. NELSON.

SEWING MACHINE.

APPLICATION FILED MAR. 2. l9l2.

1,%88,65Q Patented Dec. 24, 1918.

7SHEETSSHEET 3- his ATTORNEY G. W. NELSON.

SEWING MACHINE.

APPLICATION FILED MAR. 2, 1912.

Patented Dec. 24,1918.

7SHEETSSHEET 4.

MATTORNEY G W. NELSON.

SEWING MACHINE,

APPLICATION FILED MAR. 2. I9I2.

1 ,2,652, Patented Dec. 24, 1918.

7 SHEETSSHEET 5.

"Ill

r l W g i II I E lliii he ATTORNEY G. W. NELSON.

SEWING MACHINE.

APPLICATION FILED MAR. 2. 1912.

1 ,28,652. Patented Dec. 24, 1918.

YSHEETS-SHEET 6.

WITNESSES."

INVENTOR BY EMAC%Q Juls ATTORNEY G. W. NELSON,

SEWING MACHINE.

APPLICATION FILED MAR. 2.1912.

Patented Dec. 24, 1918.

7SHEETSSHEET I.

WITNESSES.

part

ran are GEORGE VJ. NELSON, 0F CLEVELAND, OHIO, ASSIGNOR TO THE STANDARD SEWING MACHINE COMPANY, CLEVELAND, OHIO, A CORPORATION OF OHIO.

SEWING-MACHINE.

Application filed March 2, 1912. Serial No. 681,208.

1 0 all whom it may concern:

Be it known that I, GEORGE W. NELSON,

citizen of the United States, and resident of Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Sewing-Machines, of which the following is a specification.

This invention relates to sewing machines, and particularly to that class of sewing machines in which succemive groups or series of stitches are made at separated points in the work, as for example, in button sewingmachines, etc.

/Vhile certain features of the present invention are applicable to sewing machines of-various types the main features of the invention are especially adapted to machines of the class just mentioned for forming se ries or groups of stitches at separated points in the work, and particularly to machines of this class in which a single thread is used, that is to say, in button sewing and similar machines for forming groups of chainstitches. In chain-stitch machines of this class it is customary to sever the thread on the completion of a group or series of stitches by a suitable means under the control of the operator. It has been found that in such chain-stitch machines provision must be made for certain necessary manipulation of the thread, to wit: that means must be employed for pulling off from the source of supply a sufiicient length of thread to permit the forming of the first stitch of a series without drawing down the end of the thread below the upper surface of the work, that the length of the thread beyond the needle eye at the beginning of the making of such a series of stitches should be deter mined in order that there may be no excess thread beyond .what is necessary for the formation of the first stitch, and that on the completion of a series or group of such stitches the end of the thread remaining in the material operated upon should be tied or knotted in order to prevent raveling out of the stitches.

One of the principal features of the present invention is the provision of means for controlling with precision the amount of threaddrawn off from the supply for the first stitch of a series or group andfor also Specification of Letters Patent.

pletion of the Patented Dec, 24, 1918.

order to accomplish the desired result a mechanism is preferably employed in which a thread-restraining device or thread-clamp is associated with suitable pull-off means and with a work-holder in such a manner that on the completion of aseries or group of stitches, and before the severing of the thread, and before the thread-restraining device becomes effective, a suflicient length of thread will be drawn off from the source of supply to permit the proper formation of the first stitch of the next series or group, and after the severing of the thread and after said thread-restraining device becomes effective the cut end of the thread is drawn back until the portion beyond the eye of the needle is substantially just sufiicient to permit the first stitch of a new series to be properly formed. One of the most important features of this part of the invention relates to the organization. and timing of these and othermeans for the purpose of properly controlling the pulling off, the severing and the pulling back of the thread in a machine of the general class specified.

Another feature of the invention relates to the provision of improved means for automatically stopping the machine on the completion of a predetermined series or group of stitches. The stop mechanism employed embodies suitable brakin devices I for en gaging opposite sides or aces of a suitable rotary driven member, such as the fast pulley generally employed in these machines, and in connection with these braking devices means are preferably provided for bringing the brake quickly into action when a spring or other suitable power device controlling the brake is released atthe proper point in the operation of the machine, to wit, on the compredetermined series or group of stitches.

In addition to the mechanism just described for controlling the thread and the stopping of the machine, improved means are also provided for operating a workholder, such for example, as a button-clamp, in two different paths; for positioning the loop below the work so that the needle in its descent will pass through it properly; and for performing various other operations all of which will be hereinafter described in detail and claimed and which are illustrated in the accompanying drawings, in which,

Figure 1 is a front side elevation of one specific type of sewing machine embodying the invention, to wit, a button sewing ma chine, with the frame thereof in substan tially central, vertical, longitudinal section, and showing the parts in the positions they occupy upon the automatic stopping of the mechanism;

Fig. 2 is a side elevation looking from the opposite side of the machine, showing the parts in the same positions as in Fig. 1;

Fig. 3 is a view similar to Fig. 2 of the main portions of the machine, showing the parts in the positions they occupy on the pulling off from the source of supply of a length of thread suflicient for the formation of the first stitch or loop of a new series;

Fig. 4 is a View similar to Figs. 2 and 3, showing the positions of the parts after the thread has been broken and the'excess of thread beyond the eye of the needle has been drawn back by the pull-off device;

Fig. 5 is a rear elevation of the left-hand end of the machine similar to a part of Fig. 2, but illustratin the automatic stop mechanism in the position it normally occupies, and just prior to being tripped; c,

Fig. 6 is a front end elevation of the machine;

Fig. 7 is a horizontal section and plan of the same, the section being taken substantially in the meeting plane of the sections of the main frame, but following the line 7'7, Fi 2' Fig. 8 is a substantially central, vertical, transverse section of the lower portion of the machine, the section being taken in line 8-8, Fig. 7, looking in the direction of the arrows;

Fig. 9 is a similar view, the section being taken in line 99, Fig. 7, and looking in the opposite direction, as indicated by the arrows;

Fig. 10 is an enlarged detail illustrating the construction and positions of a threadrestraining device or thread-clamp which will be hereinafter described;

Fig. 11 is an enlarged detail illustrating in plan the construction and mode of operation of the loop ositioner, looper. etc., and

Fig. 12 is a etail illustrating the construction and operation of one of the braking devices of the automatic stop mechanism.

Similar characters designate like parts in all the figures of the drawings.

While various features of the invention may be embodied in various specific types of sewing machines, as before stated, most of, them are specially applicable to that class of sewing machines forming .sewin machines, for which reason the vagroups of sepa-' rious eatures of the invention are illustrated in the drawings as embodied in a button sewing machine. Many of the parts of this machine are or may be similar to those of other button sewing machines heretofore used, such for example, as the Standard button sewing machine. In the machine shown the mainframe comprises upper and lower portions, 2 and 3, suitably connected and containing suitable chambers, bearings and other openings for the reception of various parts of the operating mechanism. The main driven member, for example, is illustrated as a fast-pulley, 4, associated with a loose pulley, 5, these two pulleys being, as is usual, in the form of hand-wheels to permit them to be readily manipulated by the operator. The fast pulley 4 is shown as secured to a main driven shaft, 6, extending substantially from end to end of the lower section 3 of the casing, and carrying at its extreme forward end a looper, such as 7, of the well-known chain-stitch type. Asso- "ciated with the fast and loose pulleys 4 and 5 is suitable means for startin and stopping the operation of the mac ine, which means, as it embodies various novel features, will be hereinafter referred to in more detail. 8 and 9 designate respectively the usual needle and needle bar, the latter of which is or may be operated in a well-known manner from the main shaft 6 by suitable connections, as indicated at 10 and 11. Suitable means are also employed for efiecting the tensioning, taking-up and guiding of the thread in the normal operation of forming successive stitches, 1212 indicating a pair of tension devices located on top of the machine arm, 13 a take-u device carried and operated by the needlear, and 14, 15, 16, 17, and 18 a series of guides for properly directing the thread in 1ts passage from the source of supply to the needle, all being of substantially usual construction and operation as found in machines of thiskind. In such machines there is also adjacent to the needle and looper a suitable work-holder or button-clamp which in many respects is or may be' similar to button-clamps as heretofore used. As the construction and operation of this button-clamp embodies, however, various features of novelty this mechanism will be also described in detail hereinafter.

Referring first to Figs. 1 and 2, t indicates the usual needlethread, which in this case is the single thread of a chain-stitch buttonsewing machine. This thread is passed through the guides, tension devices, take-up device, etc., in the manner illustrated in detail in these views and in Fig. 6. As is well known, in all machines of this type a series or group of stitches is made, as for Laeaeaa example, in sewing on a button, and the machine is then-brought toa stop, usually by an automatic stop mechanism. On the stopping of the machine the operator then usually has to perform one or more operations manually in order to complete the work being done at one point in the length of the material operated upon and then has to shift the work to a new position.

One of the'principal features of the present invention relates to means, preferably under the control of the operator, for manipulating and severing the thread after the stopping of the machine. operations to be performed are the pulling or drawing ofi" from the source of supply, preferably before the severing of the thread, of a length of thread sufficient for the formation of the first stitch of a new series after the severing of such thread, the severing of the thread at the end of such COIH- pleted series of stitches, and the drawing back or taking up of any excess of thread projecting beyond the eye of the needle after the thread has. been out. In order that the operator may properly control these various actions, suitable means are provided for pulling off the desired length of thread for making the first stitch of a new series, for restraining the thread against feeding movement from the source of supply aft-er the desired amount has been pulled ofi from the latter, for effecting the severing of the thread at or beyond the end of the series of completed stitches, and for pulling back the long severed end of the thread through the eye of the needle until only a sufii'cient length of thread is left beyond said eye to permit the proper formation of the first stitch of a new series.

All of the devices just referred to are preferably under the control of the operator through a single controlling or oper ating device, such as the lever, 21, pivoted on the head of the machine at the rear side thereof. This lever may be operated in any suitable manner, as for example, by connections such as 22, leading to a treadle or other operating element. By means of this controlling or operating lever 21 and connections thereto all of the devices just referred to, to wit, the means for pulling the thread both before and after it is cut, the means for restraining the thread, and the means for severing the thread near the work, may be operated, and in the desired timing. The particular construction of these devices may be varied at will. 23 designates generally a pull-off device which in this case serves not only as a means for pulling additional thread from the spool, but also as a means for pulling back the cut end ofthe same thread through the eye of the needle to measure the length of the initial end of the thread to be passed into or through the The principal work. 24 designates generally a threadrestraining device or thread-clamp adapted for engaging the thread at a suitable point in the rear of the needle and also in the rear of the pull-off device 23. Here the looper 7 or rather the hook thereof constitutes the immediate means for severing the thread on the completion of the predetermined series or group of stitches. This cutting of the thread is, however, due specifically in the present machine to the raising of the work-holder, designated generally by H, the resulting strain on the thread which is held against feeding movement'at such time by the action of the thread-restraining device 24 being such that the sharp edge of the hook of the looper serves to cut the thread-when the work-holder H is raised. This lifting movement of the workholder is permitted in the present case by pivoting said work-holder at its rear end,

as indicated at 20.

The pull-off device 23, as illustrated, is in the form of an angle lever pivoted to the head of the machine at the rear side thereof and being formed at one end with an angular extension arranged to engage the thread between two fixed guides 19, 19, on the faceplate of the machine as shown, the said extension being provided with an eye 23 for effecting engagement with the thread.

This lever is here shown as being slotted at 25, to permit adjustment of the length of the arc of movement of its working end. A

link, 26, is shown as connecting the adjustable end of this pull-0H lever to the forward end of the operating lever 21. This pull-ofi device is normally; held in its ineffective position in some suitable manner, as for example, by. a spring 27, secured at one end to said lever and at the other end to the head of the machine.

The thread-restraining device or threadclamp 24 is here shown as a short lever pivoted in a recess in the top of the head or overhanging arm of the machine at a point between the tension devices 12, 12, and as joined by a short connector or rod, 28, to the lever 21 at a point much nearer the pivot 29 of said lever than the link 26 connected to the pull-off device before described. The action of this thread-restraining device or thread-clamp is suitably regulated and. cushioned by adjusting and c eck nuts and aspring, such as 30, 31 and 32, the construction and use of which will be clear (see particularly Fig. 10). The thread If is intended to be clamped between the member 24 and a bed Plate of the machine. Preferably the connections employed for this purpose will also be operated from the lever 21 and in proper timing withrespect to the pull-off device 23 and the thread-restraining device 24. In this case the connecting means between the lever 21 and the work-holder embodies a chain or other suitable device, such as 34, for introducing an idle movement, that is to say, for permitting some lost motion in order that the severing of the thread may take place in proper timing with respect to the other operations.

Thus it will be seen-that in the construction illustrated the means for pulling off from a source of supply a length of thread suflicient for the making-of the first stitch of a new series, the clamping of the thread so that no more can be pulled off at that time from the spool, the severing of the thread near the work, and the pulling up from the work through the eye of the needle of any excess of thread that may project through the eye of the needle, are all preferably effected from a common actuating device under the control of the operator. The proper timing of these various operations is a matter of much importance as the thread must be free at the clamp 24 when thepullofi' device 23 operates to pull off from the spool the necessary length of thread for the formation of the first stitch of a series, and the clamp must be effective to grip the thread not only when the work-holder is lifted to sever the thread and release the work, but also when the pull-ofi device operates to pull the thread back, that is, in the reverse direction, through the eye of the needle. The extent of movement of each of the three main elements just described, to wit, the

pull-01f means, the thread-clamping device,

and the work-holder-lifting means, may also be properly adjusted and controlled with respect to the movement of their common actuator, notwithstanding the fact that the extent of movement of each of these three devices for the four main operations just described is different, and notwithstanding the fact that their movements take place in different timing. The control of their move ments results here from the connection of the various devices to the lever 21 at different points in the length of the short arm of said lever and from the provision for necessary lost motion. By properly combining and timing the movements of these various devices in the manner disclosed, the operator may, by a single quick movement of the lever 21, move said devices from their normal positions shown in Fig. 2, first to the various positions indicated in Fig. 3, at which time the pull-off device 23 has drawn from the spool the necessary length of thread for the formation of the first stitch of a series and the thread restraining device 24 has moved from its dotted-line position in Fig. 10 to its full-line position and just clamped the thread to restrain it against further feeding movement in a directiontoward the needle, after which said parts will be moved to the limit of their movements withthe lever 21' against the stop 35, as indicated in Fig. 4, at which time the work-holder has een raised and effected the severing of the thread across-the looper-hook and the pull-off device has drawn the severed end of the thread eye of the'needle to the proper point, all in .quick succession.

At the beginning of the operation of the machine on the work, and at the beginning of the operation of making any new series or group of stitches 'in 'the work, as for example, in sewing on a button, such as b, the parts .just described will occupy the positions shown in Fig. 2. At this time, however, the

starting and stopping mechanism will not be in the position illustrated in Fig.2 but will be in the position shown in Fig. 5. One of the principal features of the improved starting and stopping mechanism embodied in the v machine shown is the provision of means for engaging the principal driven member or fast pulley 4 at opposite sides thereof when the machine is to be automatically stopped. T'wo braking surfaces are provided for this purpose, which surfaces should of course be clear of said driven member when the machine is in operation. The two braking devices may be of any suitable construetion and may be operated in any desired way so long as they are constructed and operated in such a manner as to clamp said driven member between them when the machine is to be stopped. The stopping means will, however, preferably include a suitable quick-acting device, such as a strong spring, for applying these braking devices substantially instantaneously to opposite sides of said driven member when the machine is to be stopped. In the construction shown the fast and loose pulleys are forced into engagement with each other by a suitable starting lever, such as 36, having in line with the center of the pulley 5 a cone-pointed pin '37, holding the two pulleys firmly together during the time that the operator desires the machine to be running. Associated with the pulleys 4 and 5 is shown another lever, such as 38, of substantially ring form surrounding said pulleys (see Fig. 7). In this case the two levers 36 and 38 are substantially parallel to each other and suitably ivoted at corresponding ends to the lower iialf frame of the machine. At 1ts upper end the starting lever 36 is shown as havlng a forwardly and downwardly extending or overhanging arm, 39, the inner face of the depending portion of which carries a suitable frictional or braking device, 40, in juxtaposition with the forward side of the pulley 4. The ring-shaped leve 38 is also shown as having near the upper side thereof a corresponding frictional or braking device, 41, substantially in horizontal alinement with that shown at 40. These two levers 36 and 38 andthe braking devices or pads carried thereby are intended to be moved simultaneously in opposite directions, the main portions of said levers, that is, the levers proper, moving away from each other to apply the brake and moving toward each other when the brake is removed and the pulleys coupled together. Any suitable means may be employed for operating said levers in this manner provided that said means is suchas to effect a quick and powerful application of the brake. In order to accomplish this a toggle connection is preferably combined with ,a strong s ring, 44,

the latter serving to effect a quic application of the braking devices 40 and 41 to the pulley 4,.while the toggle serves, to obtain a powerful grip through said braking devices upon t e opposite sidesof said pulley 14. A toggle connection suitable for this purpose. is indicated herein, comprising in this case a pair of links, 42 and 43, connect ed respectively to the starting lever 36 and t afixed point on the upper frame 2 of the machine, the links of the toggle at their point of connection being also pivoted to a third link, 44, the upper end of which is in turn pivoted to a rock-arm 45* of a rock shaft, 45, journaled in bearings in lugs projecting from the up er rear end of said mainframe 2, said rock 3 aft also having secured thereto at its front end two rock arms, 46, and 47,'and at its rear end a rocking pawl 4.8. The rock arm 46 is intended to be operated by connections from a treadle or other suitable part to start the machine, while the rocking pawl 48 constitutes one element of a holding device or detent, and is adapted to be engaged by a complementary holding element or detent, which in the present case is the hooked upper end, 49, of a long lever, 50, pivoted near the center on asuitable fixed portion of the frame of the machine, and having its lower endsuitably facedor beveled, as indicated at 51,- for cotiperation with tripping means which will be hereinafter described.

The rock arm '47 is shown as connected by means of a rod, '52, to the free end ofa rock arm, 53, secured to one end of a rock shaft, 54, journ'aled in bearings at the rear end of the machine and having a pair of eccentrics, 55, formed thereon for cooperation with the forward ends of a pair of substantially horizontal links, 56, the rear ends of which are connected to the ring-shaped lever 38. near the upper end thereof. The construction of these parts and the mode of organization thereof is such that when thestarting lever is moved rearwardly or in a direction to release the driving pulley from the. driven pulley the toggle is straightened,

and at the same time, through the connections from the rock shaft 45 to the rock shaft 54, the links 56 are moved forward slightly by the eccentrics 55, their movement being small as compared with the rear- -W3.Id movement of the starting lever, and

nection with these braking devices means will preferably be employed for assuring the stopping of the machine each time with all of the parts in a predetermined position, to wit, with the take-up 13 in raised position to take the first stitch of the next succeeding series. The means here used for this purpose is a wedge for increasing the friction opposed to the rotation of the parts at a predetermined point. Such a wedge or cam is shown at 4 on the pulley 4'and coiipcrates with the braking device 40 on the starting lever 36 and the braking device 41 on the ring-lever 38 to wedge said pulley between said braking surfaces and bring the machine quickly,but with a properly graduated action, to a stop at the exact point desired. To start the machine the operator presses 'down a treadle' or other suitable device and through suitable connections, one of which is shown at 57, to the rock arm 46, the rocking pawl 48 is drawn down until it passes below the hook 49 of the detent lever 50 when it is engaged by said hook or detent,

' as shown in Fig. 5, which is normally forced toward said rocking pawl, as by means of a spring 58. This movement of the connect effecting the tripping of the devices Just described. Preferably, however, suitable releasing or tripping means operated from the main shaft 6 through a cross shaft, such as 59, will be employed. Here this cross shaft is journaled in suitable bearings in the lower frame member 3 of the framing, and is driven from the main shaft by suitable gearing, such as the worm-gearing 60 and 61, by means of which a relatively slow rotary movement is imparted to said cross shaft 59. On the completion of the making of a predetermined number of stitches a suitable releasing device may bebrought into operation by said cross shaft. In the construction shown said cross shaft carries at its rear end a relatively thick disk 62, in which one or more radially movable pins, such as 63, may be supported for sl ding movement. These pins may be held either in or out of operative positionas by suitable' clamping devices, such as 64. Where a single pin projects, as shown in the drawings, the automatic stop mechanism w1ll be tripped onceon each complete rotation of the cross shaft 59; whereas if both of the pins shown so project said stop mechanism will be tripped twice on such rotation of the.

cross. shaft. fBoth of these pins may be drawn in and securely clamped out of ac tion when it is desired to use the machinefor straight-away stitching without automatic stoppage of the mechanism periodically. On the completion of the predetermined rotary movementof the shaft 59 and the disk 62, that is, on the completion of the making of the predetermined series or group of stitches, the pin 63 will come in contact with one of the faces 51 of the detent lever and release the lever from the rocking pawl 48, whereupon the automatic stopping of the mechanism will ensue. as previously described. The trippingnmeans illustrated is shown as normally covered by a swinging plate, such as 65.

4 An important feature of the mechanism of the present machine is the means employed for operating the work-holder or button-clamp and "controlling the movements thereof in its different paths. The work-holder itself isor may be any suitable for the purpose. In the construction shown a button-clamp is illustrated which has three button-holding jaws, two of which are sidejaws. 6666, and the third'of which is an end jaw, 67. These jaws are normally held in the position shown, for example in Fig.

7, a spring being illustrated at 68 for normally holding the jaws together and suitable operating connections,-such as a rocking frame 69, and a slide operated thereby, being employed for spreading the jaws 66 and withdrawing the jaw 67. This is accomplished in the construction shown by the oscillation of the rocking frame 69 about its pivot on the work-holder, said rocking frame having'a rearwardly extending lever arm, 71, co-acting with a fixed member or resistance actuator, 72, on the frame of the machine, the parts being so constructed and combined that on the lifting of the workholder the frame 69 will turn about its pivot and will draw back the slide 70, which lat-- ter has a pair-of cam grooves, 73, for coacting with pins on the jaws 66 to spread the latter when the slide is so operated.

The button-holder and the parts for oper-. ating the same which have just been described, are pivoted to oscillate up and down about an axis on the button or work holder slide. This slide, designated generally by 7 4, is intended to have movements both backward and forward and sidewise forthe purpose of properly positioning the button I) beneath the needle 8. It is pivoted at -(see Fig. 1) in the fixed frame work or bed plate of the machine for turning movement and it is also slotted longitudinally for lengthwise movement relative to said p1vot pin or screw tively connected to the rear end of the workholder slide by means of a pivoted block 79" on its under side engaging the work-holder slide within an elongated slot therein (see Fig. 7). The two transverse slides 78 and 79 are intended to be reciprocated by suitable connections from the main shaft 6. The connections shown comprise a pair of angle levers, 80 and 81, operatively connected at their upper ends respectively tothe transverse slides 78 and 79 and suitably pivoted for movement about their axis, 82, which 'is in a rock shaft supported in the lower portion of the frame of the machine. These two angle levers cooperate respectively with a pair of sleeves or collars, such as 83 and 84:, mounted on a fixed shaft, 85,

and slidable on said shaft and having peripheral cam surfaces cooperative with the respective levers 80 and 81 as the case may be. One of these collars has a cam 86 and the othera pair of cams 87 and '87. Each collai' has in fixed relation therewith a spurwise of the fixed shaft 85 and to a certainextent independently'of the other, that is to say, each collar, etc., is movable along said fixed shaft in its proper timin but in all positions on the s aft said: col ar with its parts is rotated constantly through its gear y the shaft 6. For the purpose-of controlling the shifting movements of these collars, etc., a pair of levers, 92 and 93, will be employed, each lever having at its lower end a reac es pin entering a circumferential guide-groove in one portlon of the collar. At their upper ends said levers are joined by connecting rods, such as 94 and 95, to the upper ends of a pair of controlling levers, designated generally by 96 and 97, suitably pivoted about a transverse axis, such as 98. At their rear ends the levers 96 and 97, which are of angular type, carry antifriction rolls which ride upon the peripheries of a pair of cams, such as 99 and 100, secured to the transverse shaft 59 hereinbefore described in connection with the automatic stop mechanism. These two cams have their cam surfaces arranged diiferentially as will be seen by referring particularly to Fig.1. It will also be notlced that each of the connecting rods 94 and 95 between the pairs of levers just referredio has a yielding or spring connection with suitable means for regulating the tension, the springs of these connections being designated respectively by 101 and 102. Each of the levers 96 and 97 is also normally held in contact with its cam as by means of a suitable spring, these springs being shown at 103 and 104. 7

By means of the connections just described movement is transmitted from the cross the levers 96 and 97 and the connecting rods 94 and 95, and the levers 92 and 93 to the collars on the shaft 85, which collars are by the action of said connections shifted in proper timing, but differentially, to permit the levers 80 and 81 to swing about their pivots from the tops to the bottoms of their respective cam faces on said collars and vice versa, for the purpose of shifting the slides 78 and 79 crosswise, of the machine, the slide 78, through the angle lever 77, and connecting rod 76 serving to shift the work-holder slide back and forth lengthwise of the machine and the slide 79 serving directly to oscillate the work-holder slide back and forth crosswise of the machine, in the proper manner for presenting one or another of the four holes in the button in position for the passage of the needle. At the beginning of the making of 'a group of stitches the workholder slide is shifted back and forth lengthwise of the machine by the crosswise movements of the slide 78, and is also oscillated about its pivot by the reciprocation of the slide 79 in a direction opposite to that of the slide 78, for the making of stitches connecting two diagonally opposite holes. On the completion of the set of stitches connecting this pair of holes the collar 84 is shifted on its shaft to transfer the lever 81 from the cam- 87 to thecam 87. The cam 87 serves to bring about a reciprocation of the slide 79 opposite to its former movement and-in harmony with the direction of movement of the slide '78 instead of in opposition to it, This causes the button to be presented in such a manner asto permit the making of stitches connecting the other pair of diagonally opposite holes. On the completion sewing on of a new button and the collar 83 x to the idle position or round part of the shaft topermit the making of a stitch or stitches in one hole ofthe' button with the work-holder slide stationary, this stitching serving to form the usual knot in the thread, after which the machine is automatically stopped as before described.

In connection with the devices just de scribed suitable means are preferably employed for normally holding the levers and 81 in contact with the cooperating portions of the sliding elements or collars with which they are in engagement. The means here shown as provided for this purpose comprise a pair of springs, 105 and 106, connecting at one end with said levers 80 and 81, and at their opposite or lower end connecting with a rod, 107, which may be loosely held against the end walls of undercut vertical grooves in the frame work near the base of the machine.

Suitable means will also be provided for normally holding the button-clamp or workholder H down in its operative position in opposition to the pull of the work-holderlifting means, which in thiscase includes the chain 34.. The means here shown for keeping the work-holder in its operative position comprises avertical post or fixed rod secured to the upper side of the buttonclamp near the center thereof and working at its upper end in-an opening in the underside of the overhanging arm of the machine. This post or fixed rod is indicated at-108. Around it is shown a coiled spring, 109, by means of which the button-clamp is normally held down. Said spring works between the under side of the overhanging head and a sto 110 on the rod 108 which stop may be ad ustable as shown.

In a machine of this class, that is, a single thread sewing machine in which there is a relative movement between the work and the looper tending to draw the loop engaged by the looper in a lateral direction from its normal and proper osition for cooperation with the needle an looper, which movement in the present caseis caused by vibrating the work relatively to the path of the needle, it is usual to provide a device for engaging the thread loop between the looper and the work to resist the said lateral drawing action on the loop and maintain its in position for proper cooperation with the needle and looper, or in other words, maintain it in position whereby the looper in its rotation will take the succeeding loop delivered by the needle and carry it through, said preceding one wh1ch latter willthen be cast ofi the looper and around the new or second loop. A device suitable for this purpose is shown in Fig. 1, associated with the parts with which it cooperates and with which its movements are timed, and is illustrated more in detail 1n Fig. 11. This thread-loop positioner is preferably mounted to move lengthwise of the machine, that is to say, substantially in the direction of the longitudinal axis of the looper shaft 6, and it is also-shown'as having a transverse movement with respect to this looper shaft axis. Here the positioner is preferably of the type indicated at 111, the'extre'me'fforward end thereof being reduced and curved as illustrated clearly in Fig. 11 to form a finger, 112, which, when be withdrawn at the proper moment from such position after the enchaining of the loops has been effected. The positioner here shown is supported on, and dlsposedlength wise of, a carrier, such as 113, mounted for operation in aspace between the underside of the bed-plate of the machine and the upper side of the forward bearing for the looper-shaft. Said carrier is here illustrated as pivoted at 114 on top of the block. or support in which said forward bearing is formed and has an oscillating movement about said pivot. This oscillation is shown as controlled by an eccentric, 115, carried by the shaft 6 and in engagement with downward extensions of the carrier 113. The eccentric just fills the space between the members 116. and serves to oscillate the carrier 113 positively back and, forth at each rotation of the shaft 6. The longitudinal movement of the positioner 111 is preferably obtained by means of a cam with which a pin, 117, at the under side of the posi- Here the shaft ,6 has at its tioner co-acts. forward end immediately in the rear of the looper 7, an enlargement or attachment of large diameter, in which. is cut a circumferential cam groove, 118, the cam portion of which serves to shift the positioner 111 back and forth at the proper points in the rota- .tion of'the shaft 6, while the portions of the groove 118 at a right angle to the axis ofthe shaft serve to hold said positioner in its operative position a sufficient length of time to enable the needle to pass through the loop positioned thereby.

What I claim is:

1. A sewing machine, comprising means for forming a group of stitches and severing the thread on the completion of the stitches of said group, said means including a needle, and a device operative at the complestitches and severing the thread at the end of said group at a point near said button clamp. said means including a needle, and a device operative at the completion of said group of stitches and prior to the commencement of th next group for pulling back through the eye of-the needle a predetermined length of the loose cutend of said thread.

3. A sewing machine, comprising means for forming a group of stitches and severing the thread near the work on the completion of the stitches of said group said means including a needle, in combination with the followin instrumentalities successi el efg th d rea fective in the order named viz.a restraining device, and a device operative at the complet on of said group of stitches and prior to the commencement of the next group for pulling back through the eye of said needle a predetermined length of the loose cut end of the thread.

4. A sewing machine, comprising means for formmg a group of stitches and severing the thread near the work on the completion of the stitches of said group, said means including a needle, and a work-holder, in combinat on with the following instrumentalities successively effective in the order named viz.a thread-restraining device connected with said work-holder, and a device operative at the completion of said group of stitches and prior tothe commencement of the next group for pulling back through the eye of the needle a predeterthe loose cut end of said holder and with the thread-restraining device operative at the completion of said group of stitches and priorto the commencement of the next group for pulling back through the eye of the needle a predetermined length of th loose cut end of said thread.

6. A sewing machine, comprising a button-clamp, means for forming a group of stitches and severing thethread at the end of said group at a point near said buttonclamp, said meansuincludin a needle, in

combination with the followmg instrumen- A90 talities successively efi'ective in the order named viz.--athread-restraining device, and a pull-ofi' devic between said button-clamp and the thread-restraining device operative at the completion of said group of stitches and prior to the commencement of the next group for pulling back through the eye of said needle a predetermined length of the loose cut end of said thread.

7, A sewing machine, comprising means for forming a group of stitches and severing the thread near the work on the completion of the stitches of said group said means including a needle, and a workholder, in combination with the following instrumentalities successively efi'ective in the order named viz.-.a thread restraining device for holding the thread against feeding movement, work-holder-liftin g means, and a devlce operative at the completion of said group of stitches and prior to the commencement of the next group for pulling back through the eye of said needle a predetermined length of the loose cut end of said thread.

8. A sewing machine, comprising a'button-clamp, means for forming a group of stitches and severing the thread at the end of said group at a point near said but-tonclamp, said means including a needle, in combination with the followin instrumentalities successively efi'ective 1n the order named viz.a thread-restraining device for holding the thread against feedin movemeht, means connected therewith ior lifting the button-clamp, and a device connected with said button-clamp and with the thread-restraining device operative at the,

completion of said group of stitches and prior to the commencement of the next group for pulling oack through the eye of the needle a predetermined length of the loose cut end of said thread.

1 9. A sewing machine, comprising a workholder and means for forming a group of stitches and severing the thread, said means including a needle, in combination with normally inefiective pull-0E and thread-restraining devices the former of which is operative on the completion of said group for pulling ofi thread before said threadrestraining device becomes efiecti-ve and is also operative at the completion of said group of stitches and prior to the commencement of the next group for pulling back through the eye of said needle a predetermined length of the loose cut end of said thread While said thread-restraining device is effective.

10. A sewing machine, comprising means for forming stitches and severing the thread said means including a needle, and means for pulling ofl thread for a stitch and thereafter and subsequent to the severance of the thread and prior to the next stitch-forming loose cut end of said thread.

12. A sewing machine, comprising means for forming a group of stitches and severing the thread on the completion of the stitches of said group said means including a needle, and means operative on the com pletion of said group for first pulling ofl thread for a stitch, thereafter and subsequent to the severance of the thread restraining the thread and then and prior to the commencement of the next group pulling back through the eye of the needle a predetermined length of the cut end of said thread.

13. A sewing machine, comprising means for forming stitches and severing the thread, said means includin a needle, a thread-restraining device, an means for pulling oil thread for a stitch While the thread-restraining device is in its ineffective position and for pulling back through the eye of the needle prior to the commencement of the next stitch-forming operation a predetermined length of the loose cut end of said thread when said thread-restraining device is in its efiective position.

14. A sewing machine, comprising means loose cut end of said thread when said thread-restraining device is in its effective position. v

15. A sewing machine, comprising means for forming stitches and severin the thread, said means including a need e, a workholder, a thread-restraining device, and a pull-ofl' device connected with said workholder and with the thread-restraining device for pulling ofi' thread for a stitch While the thread-restraining device is in its ineffective position and for pulling back through the eye of the needle prior to the commencement of the next stitch-forming operation a predetermined length of the loose cut end of said thread when. said thread-restraining device is in its effective position 16. A sewing machine, comprising means for forming a group of stitches and severing the thread on the completion of the stitches of said group said means including a needle, a thread-restraining device, and means operative on the completion of said group for pulling off thread for a stitch while the thread-restraining device is in its ineffective position and for pulling back through the eye of needle prior to the commencement of the next group of stitches a predetermined length of the loose cut end of said thread when said thread-restraining device is in its effective position.

17. A sewing machine, comprising means for forming a group of stitches and severing the thread on the completion of the stitches of said group said means including a needle, and a device operative subsequent to the severance of the thread and prior to the commencement of the neiit group of stitches for pulling back through the eye of the needle a predetermined length of the loose cut end of said thread.

mally ineffective pull-01f and thread-restraining devices the former of which is located between the thread restraining devices and the eye of the needle in the lead of the thread and is operative on the comple tion of said group and during one movement of the same to first pull off thread before said thread-restraining device becomes effective and thereafter pull back through the eye of the needle a predetermined length of the loose cut end of said thread While said thread restraining device is effective.

Signed at Cleveland, in the county of Cuyahoga, and State of Ohio, this 27th day of Feb, A. D. 1912.

GEORGE W. NELSON.

Witnesses: I

CHAS. G. EMMONS, W. C. WALKER. 

